+ 2 1 1 2 ⃑⃑⃑ ⃑⃑⃑⃑ 2 1 ( ) 2 = √ + 2 θ = tan −1 ( ) = + 2 1 = cos 30° + cos 60° 2 1 1 √3 = (5.0 ) ( ) + (4.0 ) ( ) 2 2 = 4.33 + 2.0